1. Field of the Invention
The present invention relates to a dish washing machine. More particularly, to a dish washing machine capable of improving spatial utilization of a washing tub through the enlargement of the washing tub and controlling the amount of wash water based on the quantity of dishes at the time of washing the dishes.
2. Description of the Related Art
A conventional dish washing machine is a machine that automatically washes dishes using cold water or hot water. A conventional dish washing machine includes a machine body, a washing tub formed in the machine body, baskets mounted in the washing tub, and main, middle, and sub nozzles mounted at the upper part, the middle part, and the lower part of the washing tub to inject wash water, which is disclosed in Korean Unexamined Patent Publication No. 2006-27096.
At the bottom of the washing tub is mounted a sump to receive wash water and pump the wash water to the respective nozzles. The sump includes a sump housing forming the external appearance of the sump, a heater mounted in the sump housing, a washing impeller disposed in the sump housing to pump wash water, a channel to guide the wash water pumped from the washing impeller to the respective nozzles, a channel control valve mounted in the channel to control the flow of wash water, and a pump motor mounted at the outside of the sump housing to drive the washing impeller.
In the sump housing is disposed a heater receiving part, which is formed in the shape of a square pool. The heater is received in the heater receiving part. At the outside of the sump housing is disposed a drainage pump, which communicates with the heater receiving part.
When dirt mixed with wash water is left in the heater receiving part, the drainage pump is operated such that the dirt and the wash water are discharged to the outside. However, the bottom of the heater receiving part is flat, and the dirt is caught by the heater. As a result, it is difficult to completely discharge the dirt.
When dirt is left in the heater receiving part due to the structural problems of the heater and the heater receiving part, bad smells are emitted from the dirt and bacteria propagate, which are great sanitary problems.